Three-dimensional Printing (3D printing) technology has been developed for about three decades, the prototyping of the printed object is based on a digital file, and the printed object is formed layer by layer with a pile of metal or plastic to duplicate an actual three-dimensional object. Therefore, for the objects which require the precision machining, such the manner can effectively reduce the production time and improve accuracy.
Before printing system starts to print, it needs to obtain a digital three-dimensional model of the object to be printed. Then, the three-dimensional model is divided into a plurality of sections so as to the print device can laminate the object layer by layer. The prototyping methods of the print device includes selective laser sintering, fused deposition modeling, stereo lithography, electron beam melting, laminated object manufacturing, laminated object manufacturing and so on. One of the main differences between aforementioned methods is that the selection of the materials, some of them are thermal plastic or softened plastic, and some are liquid material.
In aforementioned manner, the printing device mainly outputs the aforementioned materials to form the cross-section of the three-dimensional model layer by layer. Each droplet size of the material is calculated in microns, theoretically, a variety of three-dimensional objects with great precision can be obtained.
However, the complexity of calculation of printing path in current 3D printing systems using layering technique remains a drawback. Because of the outputted solidified material requires to support for each other to form a three-dimensional object, and the calculation also needs the algorithms for forming outer wall and extra support to complete the printing. However, the complex calculation will reduce the operation speed of the printing device and the development of calculator also requires additional expense. Since the droplet size of the outputted material is calculated in microns, it also means that the surface smoothness of the printed object is only in micron order, such that the resolution of the three-dimensional object which is formed by current 3D printing system is limited and the surface smoothness of the object is not able to meet a higher standard of smooth degrees, for example, the formation of nano-scale surface.